You do know I linked to it earlier in this thread, right? What's considered personal is quite broad. Basically it's whatever the president says it is.
"The Court notes at the outset that there is broad language in Armstrong I stating that the
PRA accords the President “virtually complete control” over his records during his time in
office. 924 F.2d at 290. In particular, the court stated that the President enjoys unconstrained
authority to make decisions regarding the disposal of documents: “[a]lthough the President must
notify the Archivist before disposing of records . . . neither the Archivist nor Congress has the
authority to veto the President’s disposal decision.”"
https://ecf.dcd.uscourts.gov/cgi-bin/show_public_doc?2010cv1834-13
Suck on that, Mr. "lawyer".
I guarantee them FBI agents didn't do their due diligence and research that, or if they did, they completely ignored it which is bonkers.